99942 Apophis (2004 MN4)

NEO PHA MOID ⇩ IMP ⇩ COV ★ EPH ⇩ OBS ⇩ Radar
Orbital Elements
Epoch (TDB)2025-11-21 (JD 2461000.5)
Eccentricity (e)0.1911663196 ± 2.00e+00
Semi-major axis (a)0.9223804710 AU ± 3.00e+00
Inclination (i)3.34095673° ± 4.00e+00
Long. of Asc. Node (Ω)203.89962943° ± 5.00e+00
Arg. of Perihelion (ω)126.67282559° ± 6.00e+00
Mean Anomaly (M)312.80548085° ± 2.46e-06
Mean Motion (n)1.1126206784°/day ± 5.43e+00
Perihelion dist (q)0.74605239 AU ± 3.05e+00
Aphelion dist (Q)1.09870855 AU ± 4.02e+00
Orbital Period0.88586012 yr ± 4.32e+00
NGA Modelr2
A1-3.03172826e-03 AU/d²
A2-2.37461812e-06 AU/d²
Physical Parameters
H (abs. magnitude)19.00
G (slope)0.15
Orbit Solution
SourceIAA
Solution Date2026-04-29
RMS Residual0.213″
Uncertainty0
Orbit TypeAten
MOID0.000007 AU
Observations Used8720
Oppositions2
Arc Total2004-2021
First Observation Used2004-03-15
Last Observation Used2021-05-20
Observations (10797)
Date Type RA Dec Mag Band Observatory
2011-07-02 06:09:09 C 09 38 37.47 +13 12 16.2 t 568
2011-12-17 19:42:14 C 21 43 14.77 -15 11 53.3 t J04
2011-12-17 20:11:44 C 21 43 21.45 -15 11 26.9 t J04
2012-01-10 23:57:06 C 23 51 46.46 -04 59 38.7 o H21
2012-01-11 00:11:24 C 23 51 49.45 -04 59 22.0 o H21
2012-01-11 00:25:55 C 23 51 52.51 -04 59 05.3 o H21
2012-01-11 17:49:18 C 23 55 32.82 -04 38 56.6 t 204
2012-01-11 18:39:22 C 23 55 43.17 -04 37 59.0 t 204
2012-02-16 19:45:56 C 02 42 15.30 +10 26 48.7 d B66
2012-02-16 20:39:39 C 02 42 24.70 +10 27 34.1 d B66
2012-02-17 19:30:40 C 02 46 24.77 +10 46 31.7 v B04
2012-02-17 19:52:04 C 02 46 28.45 +10 46 48.8 v B04
2012-02-18 00:57:32 C 02 47 21.87 +10 51 00.8 t H21
2012-02-18 01:18:25 C 02 47 25.45 +10 51 17.5 t H21
2012-02-18 01:25:20 C 02 47 26.64 +10 51 23.4 t H21
2012-02-18 01:32:03 C 02 47 27.81 +10 51 29.3 t H21
2012-02-20 00:56:45 C 02 55 42.01 +11 29 37.3 r H21
2012-02-20 01:06:43 C 02 55 43.71 +11 29 44.9 r H21
2012-02-21 20:49:22 C 03 03 15.33 +12 03 38.7 v B04
2012-02-22 19:11:55 C 03 07 05.37 +12 20 33.3 d B66
2012-02-22 19:38:12 C 03 07 09.97 +12 20 53.2 d B66
2012-02-26 01:23:12 C 03 20 21.84 +13 17 16.1 t H21
2012-02-26 01:32:09 C 03 20 23.35 +13 17 22.2 t H21
2012-02-26 01:41:06 C 03 20 24.87 +13 17 28.9 t H21
2012-02-26 01:52:38 C 03 20 26.73 +13 17 37.1 t H21
2012-03-02 19:51:03 C 03 43 27.01 +14 48 16.8 u B04
2012-03-02 20:32:25 C 03 43 33.74 +14 48 41.8 u B04
2012-03-14 19:38:31 C 04 29 52.80 +17 19 52.9 u B04
2012-03-14 19:52:16 C 04 29 55.00 +17 19 58.5 u B04
2012-03-14 20:06:18 C 04 29 57.20 +17 20 05.0 u B04
2012-03-23 18:36:57 C 05 03 25.35 +18 41 11.9 o 461
2012-03-23 18:47:26 C 05 03 26.91 +18 41 14.9 o 461
2012-03-23 18:57:48 C 05 03 28.50 +18 41 18.2 o 461
2012-03-24 18:45:25 C 05 07 08.23 +18 48 40.5 o 461
2012-03-24 18:58:00 C 05 07 10.16 +18 48 44.7 o 461
2012-03-24 19:09:32 C 05 07 11.89 +18 48 47.7 o 461
2012-04-20 03:34:07 C 06 41 12.81 +20 14 34.7 r G96
2012-04-20 03:35:59 C 06 41 13.09 +20 14 34.4 r G96
2012-04-20 03:37:48 C 06 41 13.34 +20 14 34.2 r G96
2012-05-08 06:11:31 C 07 42 43.055 +19 21 57.56 L F51
2012-05-08 06:18:11 C 07 42 43.972 +19 21 55.84 L F51
2012-05-08 06:24:54 C 07 42 44.881 +19 21 54.37 L F51
2012-05-08 06:31:34 C 07 42 45.811 +19 21 52.86 L F51
2012-12-03 01:22:55 C 12 06 42.880 -25 22 14.98 188
2012-12-03 01:25:07 C 12 06 42.482 -25 22 15.92 188
2012-12-03 01:27:19 C 12 06 42.048 -25 22 16.61 188
2012-12-03 01:29:17 C 12 06 41.663 -25 22 17.56 188
2012-12-03 01:30:29 C 12 06 41.414 -25 22 17.90 188
2012-12-03 01:31:40 C 12 06 41.165 -25 22 18.48 188
2012-12-03 01:32:51 C 12 06 40.956 -25 22 18.75 188
Radar Observations (50)
Epoch (UTC)ValueSigmaUnitsFreq (MHz)ReceiverTransmitter
2005-01-27 23:31:00 -100849.1434 0.25 Hz 2380 -1 -1
2005-01-29 00:00:00 192028507.13 4 us 2380 -1 -1
2005-01-29 00:00:00 -102512.9059 0.25 Hz 2380 -1 -1
2005-01-30 00:18:00 195808170.79 4.5 us 2380 -1 -1
2005-01-30 00:18:00 -103799.8178 0.15 Hz 2380 -1 -1
2005-08-07 17:07:00 8186.8 0.2 Hz 2380 -1 -1
2006-05-06 12:49:00 -118256.8 0.1 Hz 2380 -1 -1
2012-12-21 11:10:00 57992.443 0.25 Hz 8560 -14 -14
2012-12-22 11:00:00 102682986.05 0.25 us 8560 -14 -14
2012-12-22 11:00:00 57880.25 0.1 Hz 8560 -14 -14
2013-01-03 09:20:00 97449107.61 0.25 us 8560 -14 -14
2013-01-03 09:20:00 36629.285 0.1 Hz 8560 -14 -14
2013-01-03 10:00:00 97439308.71 3 us 8560 -14 -14
2013-01-03 10:50:00 97428425.46 0.25 us 8560 -14 -14
2013-01-05 08:40:00 30404.009 0.2 Hz 8560 -14 -14
2013-01-05 10:40:00 96911591.52 0.25 us 8560 -14 -14
2013-01-05 10:40:00 20031.16 0.1 Hz 8560 -14 -14
2013-01-05 10:50:00 96910218.03 3 us 8560 -14 -14
2013-01-06 08:20:00 26660.815 0.1 Hz 8560 -14 -14
2013-01-06 09:30:00 20775.144 0.1 Hz 8560 -14 -14
2013-01-08 08:10:00 15496.441 0.1 Hz 8560 -14 -14
2013-01-09 08:00:00 96451449.73 0.2 us 8560 -14 -14
2013-01-09 08:00:00 9670.119 0.1 Hz 8560 -14 -14
2013-01-09 09:20:00 2690.401 0.1 Hz 8560 -14 -14
2013-01-10 08:00:00 96472652.72 0.2 us 8560 -14 -14
2013-01-10 08:00:00 2590.857 0.1 Hz 8560 -14 -14
2013-01-10 09:40:00 96473924.8 0.2 us 8560 -14 -14
2013-01-11 07:20:00 -1589.599 0.2 Hz 8560 -14 -14
2013-01-14 08:10:00 97258343.56 0.2 us 8560 -14 -14
2013-01-14 08:10:00 -30561.776 0.1 Hz 8560 -14 -14
2013-01-14 09:50:00 97283037.17 0.2 us 8560 -14 -14
2013-01-15 06:30:00 -30666.291 0.1 Hz 8560 -14 -14
2013-01-16 06:30:00 98086754 1 us 8560 -14 -14
2013-01-16 06:30:00 -39582.277 0.2 Hz 8560 -14 -14
2013-01-16 07:50:00 -46641.384 0.1 Hz 8560 -14 -14
2013-01-17 06:20:00 -47875.142 0.1 Hz 8560 -14 -14
2013-02-18 00:56:00 -76760.475 0.2 Hz 2380 -1 -1
2013-02-18 01:37:00 157906444.15 0.25 us 2380 -1 -1
2013-02-18 01:37:00 -78041.365 0.2 Hz 2380 -1 -1
2013-02-19 01:08:00 -78105.657 0.2 Hz 2380 -1 -1
2013-02-20 00:38:00 -78070.341 0.2 Hz 2380 -1 -1
2013-02-20 01:26:00 163578875.87 0.25 us 2380 -1 -1
2013-02-20 01:26:00 -79560.965 0.2 Hz 2380 -1 -1
2013-02-21 01:04:00 -79697.13 0.2 Hz 2380 -1 -1
2013-03-15 23:59:00 235220855.07 2 us 2380 -1 -1
2013-03-15 23:59:00 -80977.5254 0.238 Hz 2380 -1 -1
2021-03-03 06:40:00 29329.8 0.4 Hz 8560 -14 -14
2021-03-05 07:00:00 112426746.52 1 us 8560 -14 -14
2021-03-08 02:50:00 112625015.08 1 us 8560 -14 -14
2021-03-11 08:20:00 113796393.86 1 us 8560 -14 -14
Station codes
-14 DSS-14 Goldstone (70-m) -1 Arecibo (305-m, 1963–2020)